JPH061694A - Diamond member and manufacturing method thereof - Google Patents

Abstract

(57) [Abstract] [Purpose] Fine-grained and dense heat resistance
The purpose is to obtain a diamond member having high oxidation resistance. [Structure] Obtained by forming a SiC layer 2 on a substrate 1 for synthesizing diamond by vapor phase growth, synthesizing a diamond layer 3 by vapor phase growth, and then removing a part or all of the base material 1. A diamond member 4 having a SiC layer 2 formed therein.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fine and dense diamond member obtained by a vapor phase synthesis method and having high heat resistance and oxidation resistance, and a method for producing the same.

[0002]

2. Description of the Related Art Diamond has properties such as high hardness, high thermal conductivity, and excellent corrosion resistance. Utilizing these properties, diamond films are mainly used for cutting tools at present. At this time, it is known that a dense film having a small particle size has good cutting performance, and heat resistance and oxidation resistance are particularly required. Further, when forming a diamond film as an ultrathin film used for an optical window or the like, a fine and dense film is required.

Conventionally, when a diamond film is formed by a vapor phase synthesis method, in order to increase the nucleation density of diamond, a diamond abrasive grain is used to damage a substrate 1 shown in FIG. 2 before vapor deposition. The diamond film 5 made of a fine and dense diamond polycrystal has been devised by increasing the diamond crystal nuclei in the initial stage of growth. Heat resistance and oxidation resistance have been improved by improving the purity of diamond crystals.

[0004]

However, the diamond nucleation density in the diamond film 5 is limited to about 10 ⁹ / cm ² and the crystal grain size is about 0.4 μm only by the scratching treatment. Further, since diamond is composed of carbon only and easily reacts with oxygen in the air at 600 ° C. or higher, heat resistance and oxidation resistance are essentially limited.

[0005]

According to the present invention, a SiC is formed on a substrate on which diamond is grown before the diamond is grown.
A layer is formed to suppress the reaction of carbon, which is to be deposited as diamond, with the substrate and its diffusion into the substrate to increase the nucleation density of diamond, and to remove part or all of the substrate. By using the SiC layer in the area where heat resistance and oxidation resistance are required, 10
A diamond member having heat resistance and oxidation resistance of 00 ° C. or higher is obtained.

[0006]

In order to increase the nucleation density of diamond to obtain a fine-grained diamond polycrystal, it is necessary to suppress carbon reaction / diffusion on / in the substrate in addition to the scratching treatment with diamond abrasive grains. In order for carbon to be effectively used for diamond growth without being taken into the substrate, it is desirable to use a material that does not easily react with carbon and has a small carbon diffusion coefficient as the substrate material.

Since carbides generally have a high melting point, they have a small diffusion coefficient of carbon and work to prevent carbon from diffusing into the substrate. Further, by using saturated carbides such as SiC, WC, and TaC, they react with carbon further. It is a suitable substrate for growing fine diamond without any damage.

When such a carbide layer is formed as a thin film on a substrate of Si, W, Mo or the like and diamond is further grown thereon, the same effect as that of a bulk carbide is obtained. By removing the above, a diamond member having a carbide coating with high heat resistance and high oxidation resistance can be obtained.

The present inventors have made Si such a carbide layer.
We have found that a thin film of C is most suitable. This Si
The thickness of the C layer must be at least 0.005 μm or more.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

As shown in FIG. 1, a 0.05 μm SiC layer 2 is formed on a mirror-polished Si substrate 1 by a known thermal CVD method. The substrate is scratched with 1500-mesh diamond abrasive grains, and then the known microwave CVD is performed.
The diamond layer 3 was grown to a thickness of 10 μm by the method.

Observation of the surface of the diamond thin film with an electron microscope revealed that the nucleation density was 10 ¹¹ / cm ^2, which was about two orders of magnitude higher than that of the prior art, and a diamond layer consisting of dense crystals with a grain size of about 0.1 μm at the end of growth. 3 could be formed.

Further, the Si base material on the diamond layer 3 is removed with an acid, and S on one side of the diamond layer 3 is removed.
A diamond member 4 having the iC layer 2 was obtained. The side of the member 4 covered with the SiC layer 2 is 100
When exposed to an atmosphere of 0 ° C. for 1 hour, no weight reduction was observed.

In the present invention, the method for growing diamond and SiC by vapor phase synthesis is thermal CVD,
Any known method such as plasma CVD may be used.

[0015]

As described above, according to the present invention, it becomes possible to form a diamond member which is fine and dense and has high heat resistance and oxidation resistance.

[Brief description of drawings]

FIG. 1 is a front view showing a state of vapor phase synthesis of diamond according to the present invention.

FIG. 2 is a front view showing a state of vapor phase synthesis of diamond by a conventional method.

[Explanation of symbols] 1 substrate 2 SiC layer 3 diamond layer 4 diamond member

Claims (2)

[Claims] 1. S on the side of at least the interface of the diamond grown by vapor phase growth on the substrate with the substrate.
A diamond member having an iC layer. 2. A SiC layer is formed on a substrate for synthesizing diamond by vapor phase growth, diamond is synthesized by vapor phase growth, and then a part or all of a base material is removed to have a SiC layer. A method for manufacturing a diamond member for obtaining a diamond member.